Download PG Evo 2005

Big Twin V2 Performance Guide
VFI Fuel Injection Module
The S&S Variable Fuel Injection (VFI) module offers
the most adjustability of any fuel injection system on the market.
S&S Variable Fuel
Injection (VFI) Module
In the old days, all a guy needed was a
screwdriver and a hand full of jets to tune his
carburetor and optimize his bike's
performance. Today fuel injection is replacing
carburetors on more and more new
motorcycles, and tuning a fuel injection
system requires a higher level of technology.
Notice:
The S&S Variable Fuel Injection (VFI™) system is only available
through certified S&S VFI Tuning Centers, except for units
purchased with complete S&S VFI equipped engines. Please
consult the dealer locator on our website www.sscycle.com to
find the S&S VFI Tuning Center nearest you.
Magneti-Marelli Style
The S&S Variable Fuel Injection (VFI) module provides tunabilty
for fuel injected Evolution engines.
The inability of the stock fuel injection system to accommodate any but the most basic performance modifications severely limits the available
options for engine builders and performance enthusiasts. S&S Variable Fuel Injection (VFI) modules restore your options and then some! S&S
VFI modules can be used to control stock fuel injection systems or may be used in conjunction with the S&S VFI induction systems for even
greater performance gains. The range of adjustment and unequaled resolution of the S&S VFI module allows tuners to compensate for any
degree of engine modification, be it ever so slight or extremely radical. Optimize the performance of a stock engine or dial in a wild one-off
custom? The S&S VFI module has the capability. Optimized tuning will improve starting, drivability, fuel mileage, and horsepower. The S&S
VFI module allows engine builders and tuners to gain the maximum benefit from time and money spent on other performance modifications,
especially when used in conjunction with the S&S VFI induction systems. See page 26-29 for more information about VFI induction systems.
Magneti-Marelli® or Delphi® Style?
Harley-Davidson has used two fuel
injection systems for their fuel injected Big
Twin engines, and occasionally there is
some confusion among riders about which
system their bike has. Harley introduced
fuel injection in 1995 with a fuel injection
system designed by Magneti-Marelli®. In
2001 Harley began using a different fuel
injection system designed by Delphi® on
the Softail models only. In the 2002 model
year, all fuel injected Harleys were equipped
with the Delphi® fuel injection system.
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It is easy to distinguish one system from
the other. The Magneti-Marelli® system has
two independent intake runners from the
throttle body to the cylinder heads. The
Delphi® system has a single throat design
with a "Y" manifold. The Magneti-Marelli®
fuel injection module is larger than the
Delphi® module used in later models. The
S&S VFI module designed to replace the
stock Delphi® module is not compatible
with the 2004 wiring and control system.
See the photos of the S&S VFI replacement
modules for a size and shape comparison.
S&S VFI modules are designed to fit in the
same space as the original units they
replace. All Evolution fuel injected models
were equipped with the Magneti-Marelli®
system. Information about the later
Delphi® system is included for custom bike
builders who wish to use fuel injection, but
are not sure which system to use. S&S
can supply either style.
email us at [email protected]